lactic acid right at the beginning of exercise

Is it normal for my calves to be using lactic acid right at the beginning of exercise and for it to then go away the longer I exercise ? I mean when I am walking fast, I get lactic acid even at the beginning of my exercise, I thought I should get that only after I've been exercising a lot at least after 30 min or more of exercise.

You received a lot of good advice on those threads. But since you are still experiencing leg pain while exercising, we strongly advise you to seek medical advice rather than continuing to post the same question over and over again here at 3FC. We can't give you medical advice and this sounds like an issue that needs professional attention.